I SPY Clair in the poster. Good to see they threw her in there. <3
I'm not ready to say sayonara to Iris! ;(
As for Butterfree, the description seems to point to a simple flashback. But at the same time, I suppose the title seems to place a substantial emphasis on Butterfree....maybe there's a twist we haven't thought of yet. I would certainly appreciate and actual encounter, if not for the sake of nostalgia, at least to provide a sense of continuity. Y'know... to show viewers that what happened a long time ago in Kanto is actually showing an effect here in the future, in Unova - or I guess in this case Decolora. It's especially rewarding to those who enjoyed watching early seasons to see them draw connections between generations.